This invention deals with heating systems, and more particularly to a microwave heating system utilizing a magnetron as the source of microwaves.
With a continuously increasing shortage in energy sources, there is a constant need for improved heating systems which can make better use of the energy source and provide a more efficient operating device. Many heating systems utilize an energy source which heats up water or other fluid and utilizes the fluid as a heat conveying substance. The fluid can either be utilized directly as in a hot water or home heating system, or alternately it can be sent to a further heat exchanger where the heat is extracted from the fluid and supplied to a further medium. However in most cases the heating system is initially utilized to heat up a fluid which serves as the heat transporting medium.
The use of microwaves for heating ovens has been found extremely effective. Such microwave ovens cook food by using short radio waves that penetrate the food and make its molecules vibrate. Friction among the moving molecules produces heat, which cooks the food. However, it is known that microwaves pass through many types of substances, such as glass, paper, and most kinds of china without heating them. Therefore, containers made of those materials may be used to hold the food in a microwave oven.
Additionally,, the walls of the microwave oven are usually made of metal since microwaves bounce off the metal without warming it.
The usual microwave ovens utilize an electronic vacuum tube, called a magnetron, in order to produce the microwaves. In many ovens, the microwaves travel through a metal tube such as a waveguide to a diffuser, such as a fan. The moving blades of the diffuser scatter the microwaves into the oven which has metal walls. The waves bounce from wall to wall until they enter food in the oven.
Although microwaves have generally been successfully utilized to provide heating of food, thus far, microwaves have not generally been commercially utilized as a source of heat for a fluid heating system.